Lavrov reiterated Russia's concerns about Turkey's request for NATO to deploy the surface-to-air missiles because of Ankara's fears of spillover from the civil war in Syria.

He said he would discuss the issue by telephone with NATO Secretary General Anders Fogh Rasmussen, who said on Thursday the alliance would "do what it takes to defend our ally Turkey".

"Apparently he (Rasmussen) wants to explain (NATO's) position on this issue," Lavrov told a news conference after talks in Moscow with Bangladesh's foreign minister, Dipu Moni.

"The main concern is the more weapons there are, the greater the risk that they will be used."

He said Russia, which is not a member of NATO and cannot block a decision, understood that no one intended to drag the alliance into the Syrian crisis.

"But ... in the military field, what is important is not intentions, but potential. And when potential increases, the risks grow," he said.

The West has criticised Russia, as well as China, for vetoing three U.N. Security Council resolutions aimed at putting pressure on Assad to end a conflict activists say has killed more than 38,000 people since protests began in March 2011.

Russia denies trying to prop up Assad, whose nation has been an avid buyer of its weapons and hosts a naval supply facility that is Moscow's only military base outside the ex-Soviet Union.